339. Nested List Weight Sum

You are given a nested list of integers nestedList. Each element is either an integer or a list whose elements may also be integers or other lists.

The depth of an integer is the number of lists that it is inside of. For example, the nested list [1,[2,2],[[3],2],1] has each integer's value set to its depth.

Return the sum of each integer in nestedList multiplied by its depth.

int depthSum(List<NestedInteger> nestedList) {
    Queue<NestedInteger> queue = new LinkedList<>();
    queue.addAll(nestedList);

    int depth = 1;
    int total = 0;

    while (!queue.isEmpty()) {
        int size = queue.size();
        for (int i = 0; i < size; i++) {
            NestedInteger nested = queue.poll();
            if (nested.isInteger()) {
                total += nested.getInteger() * depth;
            } else {
                queue.addAll(nested.getList());
            }
        }
        depth++;
    }
    return total;
}